Electrolyte-free electrochemical C-H trifluoromethylation of 2-pyridones under batch and flow conditions

Herein, we report direct C3 trifluoromethylation of 2-pyridones including unprotected derivatives by an electrochemical approach using the readily available Langlois reagent as the CF3 source in the absence of electrolytes. The trifluoromethylation under transition metal- and oxidant-free conditions occurred site-selectively to give the desired products in moderate to good yields under ambient conditions. Interestingly, significant acceleration rates, improved yields and selectivities as well as reduced energy consumption were achieved under microfluidic conditions.

Automated summary

In this study, direct C3 trifluoromethylation of 2-pyridones was achieved by an electrochemical method without the need for electrolytes. The readily available Langlois reagent was used as the CF3 source. The reaction occurred site-selectively under transition metal- and oxidant-free conditions, giving moderate to good yields under ambient conditions. Interestingly, significant improvements were observed in terms of acceleration rates, yields, selectivities, and reduced energy consumption under microfluidic conditions.